Assume that you are moving towards a complex microcontroller project bundled with blinkers, beepers, and a display panel. To link a standard 16×2 LCD directly with the microcontroller, for instance ...

The gotcha is the logic level gap between the devices. If you’ve been working with Arduino, your add-ons are probably meant for a 5V power rail and logic levels. The RPi outputs 3.3V logic.

To build this project, all you need is three main components: an Arduino Uno, a 16x2 LCD, and a push button. You can connect everything to a breadboard to keep it simple.